1. Technical Field
Example embodiments relate to CMOS image sensors, for example, to CMOS image sensors capable of outputting pixel data at a relatively high speeds and image sensing methods thereof.
2. Description of Related Art
Conventional image sensors include charge-coupled devices (CCDs) and complementary metal oxide semiconductor (CMOS) image sensors (CISs). A CIS is more economical than a CCD because the CIS can be manufactured using conventional CMOS processes. A CIS is also advantageous with respect to integration density because analog and digital signal processing circuits can be integrated into the CIS. In addition, because a CIS can be adapted to relatively low-power-low-voltage design, it is more widely used in portable devices such as mobile phones, digital cameras, personal digital assistants (PDAs), and the like, which require relatively low power consumption. A pixel array of a conventional CIS includes a plurality of pixels arranged in a two-dimensional matrix of rows and columns and each pixel outputs an image signal in response to incident light energy.